Lawnboy L21ZSN

Guys I was searching craigslist and found a new never used, never gas in the tank, still in the box Lawnboy model L21ZSN year 1992. Manual and a can of oil still in the sealed bag. This guy has had it all this time and never used it. It did not even have dust on it. It is self propelled with some kind of drive rollers? It is also a 2 stroke, Duraforce? Not sure. I bought it for the nostalgia. What would this be worth if anything? I do not want to say how much I paid yet so no one laughs at me if I took a screwing. Any ideas?
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